High speed recording apparatus for television images and the like



Dec. 17, 1968 NOBORU MASUDA 3,417,197

HIGH SPEED RECORDING APPARATUS FOR TELEVISION IMAGES AND THE LIKE Filed March 24, 1965 8005729? AMPA m5? 1 1 United States Patent 3,417,197 HIGH SPEED RECORDING APPARATUS FOR TELEVISION IMAGES AND THE LIKE Noboru Masuda, Ota-ku, Tokyo-t0, Japan, assignor t0 Denki-Onkyo Kabushiki-Kaisha, Tokyo-to, Japan Filed Mar. 24, 1965, Ser. No. 442,414 4 Claims. (Cl. 1786.6)

Optical means have been used in recording television images and the like.

This invention relates to recording apparatus wherein records of television images and the like are obtained clearly at a high speed by using an electric circuit and an electrostatic recording medium.

FIGURE 1 is an explanatory view showing the operating principle of an embodiment of the present invention.

FIGURE 2 is an explanatory view of another embodiment.

The present invention shall now be explained with reference to the drawings. In FIGURE 1. 1 is input signal amplifier having a function of amplifying also synchronous signals together, 2 is a synchronous pulse separating circuit, 3 is an image current amplifier, 4 is a synchronous pulse shaper and 5 is a printing tube. When an electronic beam projected from an electronic gun is deflected and scanned by a deflecting plate 6 and strikes a grid-shaped electrode 7 on the surface of the printing tube 5, a high voltage will be impressed on the electrode 7. 8 is an opposite electrode arranged substantially in contact with the surface of the printing tube 5. 9 is a recording medium which is fed in turn between the surface of the printing tube 5 and the opposite electrode 8 and which is made of such thermoplastic film having a high molecular structure and generally known as a polymer as, for example, polyethylene, polypropylene, polyvinyl butylal or polycarbonate by mixing in 0.1 to 0.005% of a surface active agent or an electron receptive substance in coating. That is to say, it is considered that the thus formed substance improves the recording results by the following imaginary reasons. However, it is not intended to thereby limit the scope of the present invention. The natural law of depositing a highly insulative substance about 100,41. thick on an insulator by pretreatment or mixing in should be noted. The reason for improving electrostatic deposition in pretreatment can be considered to be, for example, as follows. First of all, a thermoplastic film insulator will be electrically charged by friction or contact but such electric charge will be neutralized to be zero or substantially zero by a pretreating solution before recording. Thus, better results than by applying a high alternating current voltage before recording can be expected, That is to say, in a recording medium of favorable recording voltage-recording concentration characteristics, a noise charge made by initial friction has such low saturation limit that usually noises can be removed and, under the influence of initial noises, uniform recording results will not be obtained. A conventional electrostatic recording paper made by coating paper with polyethylene and the like has recording voltage-voltage characteristics that no intermediate tone will be produced. It is therefore comparatively easy therein to remove such initial noises as are described above. It is essentially different from the present invention. For the above described reason, in such recording apparatus as in the present invention, pretreatment is required.

Now, for the second reason, it has been considered, for example, that nonpolar substances will hardly polarize and will be hardly electrically charged by friction. However, in fact, almost all substances will be electrically charged. It is thereby possible to make an activity on the surface when impurities are deposited and to make recorded latent 3,417,197 Patented Dec. 17, 1968 images only under the surrounding conditions, that is, in the presence of air. The insulating property is only to hold the deposited electric charge and has no substantial role in depositing a large electric charge. Further, in expanding and interpreting the first and second considerations, it is presumed that, even if the thermoplastic film is not an insulator, favorable results will be obtained. That is to say, it is found that the insulation resistance has only an action of holding an electric charge and that, if such substance as will help the electric charge deposition is mixed into the thermoplastic film or the surface of the thermoplastic film is treated with such substance, favorable results will be obtained.

It can be understood that, if a substance based on the above assumption is molecularly deposited on the surface or mixed in, the resolving power will not be reduced and favorable recording results will be obtained. However, a great difiiculty is anticipated in uniformly mixing such electrolytic substance into a substantially oily, thermoplastic film. According to results of experiments, it is found that what are known as surface active agents today are effective as mixtures of this kind. As a result of repeated experiments, it was found that favorable ones are available, Therefore, the concrete formation shall be described in the following.

Such polyethylene which has few double bonds and in which is mixed about 0.08 to 0.1 part of a substance having any of the structural formulas is favorable.

For such activators are specifically favorable nonionic series polyoxyethylene castor oil ethers and polyoxyethylene laurylic acid ether series of an H.L.B. of about 3 to 14. Therefore, the following electrostatic phenomenon can be understood. That is to say, the substance inserted into the high molecular insulator has such action as of impurities and has internally partially an electric charge in the form of ions. But, as seen externally, the substantial total charge is zero. Now, if a positive charge is given from outside to the substance thus mixed in, the negative ions will be subjected to a positive charge, will come to have no ionic property and will be converted to be in the form of atoms or molecules. That is to say, as seen generally, it is considered that a positive charge will be deposited on the recording medium. This is considered from the fact that a positive charge is deposited by a positive electricity application. It is also considered to be a cause of the fact that, in case such thing is mixed in, an electrostatic charge Will be favorably deposited, On the other hand, the negative case can be considered in the same manner. Now, in the process of the movement of the electric charge, it will work as a void (mixed in) type streamer between the respective substances mixed into the film and the insulator between the respective voids will become very thin. It is considered to be one cause of the fact that results better than in the case of using, for example, a simple substance of polyethylene itself for the recording medium. What is detailed in the above is an imaginary principle. But, the fact that favorable results were experimentally obtained by mixing or applying the above mentioned substance should be respected. It shall be stressed that the scope of the right of the present invention should not be limited by said imaginary principle. 10 is a magnetic brush to deposit on said recording membrane 9 a visible substance known generally as a toner and prepared by mixing a color and iron powder into a thermoplastic film. 11 is a fixer enclosing an acetone gas (vapor). Visible images are fixed by passing the recording membrane 9 through said vapor.

In FIGURE 2, 12 is an input signal amplifier, 13 is a distributor, 14 is a boosting amplifier connected to needles, 15 is a recording membrane made by surface-treating a simple synthetic film, 16 is an electrode drum rotating at the same linear velocity as the payout velocity of the recording medium and arranged opposite a bank of high voltage contact needles 17 insulated from one another and formed to be in contact with the electrode drum 16 through the recording membrane 15, 18 is a magnetic brush to deposit a powder known generally as a toner carrier on the recording medium and 19 is a fixer enclosing such vapor as of acetone.

Now, when an input signal of a television and the like enters the input signal circuit 1, it will be amplified on a proper level, will be then led to the synchronous separating circuit and will be perfectly separated from a picture element signal in the circuit so formed that horizontal synchronous pulses may be separated from picture signals. This separated signal will be made a saw-tooth wave in the shaping circuit 4 and will be applied to the deflecting plate 6.

It is well known that an electron coming out of the electronic gun in such case is represented by the relative formula wherein Y is a deflection, V is a potential of the deflecting plate, 1 is a length of the deflecting plate, d is a distance opposite the deflecting plate and L is a distance from the deflecting plate to the printing electrode.

That is to say, an electronic beam projected from the electronic gun of the printing tube will be subjected to a deflecting action by the deflecting plate 6 and will be gradually deflected from right to left or from left to right. That is to say, as the recording medium is made of a transparent substance, the direction of such rightward or leftward operation is properly selected depending on such kind as a transmitting type, duplicating type or reflecting type duplicator. The recording result can be taken as a positive or negative image. If the input signal is in the image current amplifier 3 as in the above, the electronic beam will be accelerated in response to the strength of the signal voltage and will collide with the grid electrode 7 embedded in the surface of the printing tube 5. A high voltage will be induced in the grid electrode 7 with which the electron collides and a high voltage will be generated between said electrode 7 and the opposite electrode 8.

The recording membrane 9 of a thermoplastic film having a high molecular structure and inserted between said electrodes will be subjected to a kind of molecular polarization by said high voltage and an electrostatic latent image corresponding to the input signal will be made on a part of the recording membrane 9. The recording membrane 9 on which such latent image is made will move in close contact with the opposite electrode 8 to the magnetic brush so that any disturbance of the image by a bound charge may be eliminated. As a result of experiments, it is disclosed that it is very diflicult to bond a transparent substance of a low resistance value to the back surface of the treated body 9. Further, such antistatic agent based on a surface activator as is often used today has a penetrating action and will remarkably disturb the balance of the electrostatic deposition reinforcing agent and no favorable recording result will be obtained.

For the above mentioned reasons, such edge electrode as is adopted for conventional electrostatic recording media similar to that of the present invention can not be utilized.

Now, a toner having an electric charge of a polarity reverse to that of the latent image made on the recording membrane 9 is deposited on the magnetic brush 10 so that, when the recording membrane 9 having the latent image passes below the magnetic brush 10, the toner will be absorbed in response to the strength of the latent image. As said toner is merely deposited on the recording membrane 9 by static electricity, when the medium is passed through the fixer 11, the toner will be perfectly fixed and a perfect visible image will be obtained.

Exactly the same effect as of the first embodiment can be expected from the second embodiment shown in FIG- URE 2. However, in the second embodiment, an elecostatic latent image is made on the recording membrane 9 by applying a boosted amplified signal to the high voltage recording needles 17 set in a position corresponding to that on the transmitting side by the distributor 13.

In each of the above mentioned embodiments, the reccording membrane 9 is brought into close contact with the drum-shaped opposite electrode 8 or 16 in order to obtain a visible image without disturbing the balance between the latent image made on the recording membrane 9 and the bound electric field formed on the opposite electrode 8. By such formation, the latent image will be recorded without being substantially disturbed. Further. even if an insulator is interposed between the recording medium and the opposite electrode, the same effect will be obtained.

Thus, according to the present invention, not only a stationary recorded image can be easily obtained from a television and the like but also two or more images can be recorded at a high speed on one recording medium by using a high speed oscillograph or a time divider.

Further, the recording apparatus of the present invention can be connected with an output device of a radar automatically controlling apparatus or a digital analogue converter. Thus, clear permanent recorded images can be obtained very cheaply. Its range of application is very wide.

What is claimed and desired to be secured by Letters Patent of the United States is:

1. A high speed recording apparatus for television images and the like comprising a thermoplastic film recording medium formed of a transparent thermoplastic unilayer film, means for advancing said medium, a needleshaped electrode, a revolving back electrode synchronized with the advance rate of said medium, said medium being inserted between said two electrodes for passage therebetween, means including said electrodes for depositing a static electric charge on said medium by impressing a high voltage thereon and a colored substance is deposited in accordance with said charge on said medium rendering a visible image, and means for subjecting said medium having said visible image to a fixing solvent vapor through which said medium is passed by said advancing means.

2. A high speed recording apparatus for television images and the like comprising a unilayer recording medium made of a thermoplastic film having a high molecular structure and a pretreated surface of an active electron receptive substance, a grid-shaped or needle bank-shaped electrode, a revolving opposed electrode arranged closely adjacent to said first-mentioned electrode, means for advancing said medium between said two electrodes, means including said two electrodes for forming an electrostatic latent image on said medium by a signal on said first-mentioned electrode and for depositing a colored substance in accordance with the intensity of said electrostatic image on said medium while said medium is on said second electrode whereby a visible image is thereby 3 wherein the fixing vapor solvent is heated to a tempera- 10 ture below the melting or softening point of said medium.

6 References Cited UNITED STATES PATENTS 3,040,124 6/1962 Camras 1786.6 3,162,104 12/1964 Medley 178-6.6 3,308,234- 3/1967 Bean 1786.6

ROBERT L. GRIFFIN, Primary Examiner.

H. W. BRITTON, Assistant Examiner.

US. Cl. X.R. 34674 

